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comparison graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/BinaryConditionProfile.java @ 16852:3c114b3e08c3

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Truffle: renamed BooleanConditionProfile to BinaryConditionProfile and IntegerConditionProfile to CountingConditionProfile.
author Christian Humer <christian.humer@gmail.com>
date Mon, 18 Aug 2014 19:00:20 +0200
parents graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/BooleanConditionProfile.java@2834af86f398
children fc6f12ee71e5
comparison
equal deleted inserted replaced
16851:2db61eddcb97 16852:3c114b3e08c3
1 /*
2 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25 package com.oracle.truffle.api.utilities;
26
27 import com.oracle.truffle.api.*;
28 import com.oracle.truffle.api.CompilerDirectives.*;
29
30 /**
31 * Utility class to speculate on conditions to be never true or to be never false. Condition
32 * profiles are intended to be used as part of if conditions.
33 *
34 * Example usage:
35 *
36 * <pre>
37 * private final ConditionProfile zero = new BooleanConditionProfile();
38 *
39 * int value = ...;
40 * if (zero.profile(value == 0)) {
41 * return 0;
42 * } else {
43 * return value;
44 * }
45 *
46 * </pre>
47 *
48 * @see ConditionProfile
49 * @see CountingConditionProfile
50 */
51 public class BinaryConditionProfile extends ConditionProfile {
52
53 @CompilationFinal private boolean wasTrue;
54 @CompilationFinal private boolean wasFalse;
55
56 @Override
57 public boolean profile(boolean value) {
58 if (value) {
59 if (!wasTrue) {
60 CompilerDirectives.transferToInterpreterAndInvalidate();
61 wasTrue = true;
62 }
63 } else {
64 if (!wasFalse) {
65 CompilerDirectives.transferToInterpreterAndInvalidate();
66 wasFalse = true;
67 }
68 }
69 return value;
70 }
71
72 public boolean wasTrue() {
73 return wasTrue;
74 }
75
76 public boolean wasFalse() {
77 return wasFalse;
78 }
79
80 @Override
81 public String toString() {
82 return String.format("%s(wasTrue=%s, wasFalse=%s)@%x", getClass().getSimpleName(), wasTrue, wasFalse, hashCode());
83 }
84 }